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The Journal of China Universities of posts and telecommunications 2010年第1期17卷 106-110页

作者： JIA Bo-yong,YU Zhong-yuan,LIU Yu-min,TIAN Hong-da Key Laboratory of Information Photonics and Optical Communications,Ministry of Education,beijing university of {2. and telecommunications,beijing 100876,China [a] Key Laboratory of Information Photonics Optical Communications Ministry of Education Beijing University of Posts telecommunications Beijing 100876 China

This article puts forward a new method in calculating the band structures of low-dimensional semiconductor structures. In this study, the valence band structures of InAs/GaAs quantum ring and lens-shaped quantum dot are calculated with four-band model, in the framework of effective-mass envelope function theory. To determine the Hamiltonian matrix elements, this article develops the numerical Fourier transform method instead of the widely used analytical integral method. The valence band mixing is considered. The hole energy levels change dramatically with the geometrical parameters of the quantum ring and quantum dot. It is demonstrated that numerical Fourier transform method can be adopted in low-dimensional structures with any shape. The results of Fourier transform method are consistent with the ones of analytical integral in literature; and they are helpful for studying and fabricating optoelectronic devices.

关键词： valence band structures quantum ring quantum dot numerical Fourier transform

AN IDENTITY-BASED PERSONAL LOCATION SYSTEM WITH PROTECTED PRIVACY IN IOT

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AN IDENTITY-BASED PERSONAL LOCATION SYSTEM WITH PROTECTED PR...

A Novel Rate Control Method for Low Delay Applications

2.11 4th IEEE International Conference on Broadband Network and Multimedia Technology

作者： Chunye Hu 1 Jie Zhang 1 Qiaoyan Wen 2.1 school of science {2. university of posts and telecommunications {2. 100876 China 2.State Key Laboratory of Networking and Switching Technology {2. university of posts and telecommunications {2. 100876 China

The internet of things（IOT）has the same security requirements as traditional network,but according to the characteristics of its own,the internet of things also has some specific security features. Among these features,the flexibility of the network requires nodes to apply corresponding measures when scene *** example,in emergency situations（*** accident occurs,and a doctor is needed）,the location of the user is available,while under normal circumstances,the user’s location information is *** paper is in the background of the above scene to present an identity based system for personal location in emergency *** proposed system consists of registration subsystem,user authentication subsystem,policy subsystem and client *** system confirms the identity of the user through the user authentication subsystem and gets the level of the emergency through the policy *** it can make sure that user’s location information can be accessed only by some authorized user,and only when *** proposed system strengthens the protection of the user’s privacy while providing the location of the user,and prevents the disclosure of the users’information.

关键词： emergency situations virtual identity internet of things(IOT) privacy security

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The Journal of China Universities of posts and telecommunications 2000年第4期7卷 31-34页

作者： SHI Ke wei, CAI An ni, SUN Jing ao (school of Telecommunication Engineering, beijing university of posts and telecommunications,{2., P.R. China) school of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R. China

In real time applications, the low delay rate is an important requirement of video coding. We propose a simple low delay rate control method in this paper for such applications. In this method, target bits are divided into two parts: uncontrolled and controlled bits in the frame layer. The first part is assigned to the header, syntax and motion vectors according to that spent in the previous encoded frame. The second part is assigned to DCT coeffcients by employing a rate model for mactorblock Q P determination. Experiments show that the proposed method can achieve better performance compared with that of the test model TMN5 of H .2.3, and slightly worse performance, but with lower computation complexity, compared with that of the TMN8 of H.2.3+ .

关键词： rate cotnrol low delay H .2.3+ low bit rate video cod|

The band structures of BSb and B_xGa_(1-x)Sb alloys

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science China(Physics,Mechanics & Astronomy) 2009年第6期52卷 843-847页

作者： XIONG DePing1, ZHOU ShouLi2. WANG Qi3, LUO Li1, HUANG YongQing3 & REN XiaoMin3 1 school of Physics and Optoelectronic Engineering, Guangdong university of Technology, Guangzhou 510006, China 2.College of Information Engineering, Zhejiang university of Technology, Hangzhou 310032. China 3 Key Laboratory of Optical Communication and Lightwave Technologies Ministry of Education, beijing university of posts and telecommunications, beijing 100876, China 1. school of Physics and Optoelectronic Engineering Guangdong University of Technology Guangzhou 510006 China 2. College of Information Engineering Zhejiang University of Technology Hangzhou 310032 China 3. Key Laboratory of Optical Communication and Lightwave Technologies Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

The band structures of BSb and BxGa1-xSb alloys are studied using first-principles calculations in the generalized gradient approximation. By SQS-8 supercells to model a random alloy, the direct transition energy-gap (Γ15v- Γ1c) bowing of 3.0 eV is obtained for BxGa1-xSb alloys in x = 0-50%, in x = 0-11% the energy-gap is the band-gap and increases by 7 meV/%B with boron composition increasing; by SQS-16 supercells the bowing parameter is about 1.9 eV in x = 0-12.5%. The formation enthalpies of mixing, ΔH, are calculated for BxGa1-xAs and BxGa1-xSb alloys. A comparison of enthalpies indicates that BxGa1-xSb films with boron composition of 7% may be possible.

关键词： band-gap bowing parameter boride alloys

AN EFFICIENT MOTION ESTIMATION ALGORITHM FOR H.2.4/AVC H.2.4/AVC

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AN EFFICIENT MOTION ESTIMATION ALGORITHM FOR H.264/AVC H.264...

Ubiquitous Access Technology for Wireless Digital Home Networks

中国通信学会第六届学术年会

作者： Guo Yanjie~1,Liu Ruifang~2.(1 school of Information and Communication Engineering,beijing {2. of posts and telecommunications,beijing 100876,China 2.school of Information and Communication Engineering,beijing {2. of posts and telecommunications,beijing 100876,China)

Motion estimation plays an important role in the video compression standard,such as H.2.3,MPEG-2.4 and *** search(FS) is the most common and simple motion estimation algorithm,but owing to the FS algorithm resulting in huge computational complexity,so many fast motion estimation algorithms have been proposed instead of *** the paper,we discuss UMHexagonS algorithm, then we propose a fast ME algorithm based on *** simulation results show that proposed algorithm maintains an unnoticeable quality loss in terms of PSNR on average compared to FS and UMHexagonS but reduces motion estimation time.

关键词：

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ZTE Communications 2006年第4期4卷 40-46页

作者： Peng Mugen 1Jiang Yong 2.ang Wenbo 1(1. school of Telecommunication Engineering, beijing university of posts and telecommunications,{2., China 2. China Potevio Co., Ltd., beijing 100053, China) China China

As an important branch of telecommunication technology, digital home networks have quickly developed in recent years. Although architecture of the digital home network based on telecommunication networks has been standardized in China, only wireless access is defined to be allowable. Therefore, it becomes the focus of further research how to establish a wireless digital home network. This article proposes the concept and shows the architecture of ubiquitous access for wireless digital home networks. Moreover, key technologies for ubiquitous access are discussed here, including cognitive radio, the concept of wireless Mesh, generic link transfer mechanism, Quality of Service (QoS) guarantee mechanism, Electromagnetic Compatibility (EMC) and coexistence of heterogeneous systems.

关键词： Access Ubiquitous Access Technology for Wireless Digital Home Networks WPAN Home

Analysis on Advertising Expenditure of Operators in the 3G Market with Game Theory

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Analysis on Advertising Expenditure of Operators in the 3G M...

A Study of MPLS Hybrid Switch Based on ATM Switch

2.09中国控制与决策会议

作者： Chen Dehua~1,Tang Shoulian~2.1.school of Economics & Management,beijing {2. of posts and telecommunications,beijing 100876 2.school of Economics & Management,beijing {2. of posts and telecommunications,beijing 100876

＜正＞With the 3G-era coming,the competition in mobile communications market will increase undoubtedly. Advertisement,as an important marketing communications measure,would be playing key role in the market *** the point of view of economics,advertising have two effects:the one is convey the information,the other is *** this thesis,the author make a research about the Boxed Pigs Game of operators to 3G informative advertisement and the Competition Game of operators to 3G product function advertisement in terms of the two different economic effects,Furthermore,through the analysis of the results above,the author posed a competition strategy about operator’s expenditure to 3G advertisement as a consequence.

关键词： 3G advertisement expenditure Boxed Pigs Game market penetration

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The Journal of China Universities of posts and telecommunications 2001年第3期8卷 6-10页

作者： SHAO Xu, ZHANG Zhi-qun, DING Wei (Continuing Education school, beijing university of posts and telecommunications,{2., P.R.China) Continuing Education school Beijing University of Posts and Telecommunications

MPLS is the most successful integrating model of IP over ATM. The paper discusses some problems and their possible solutions when MPLS is supported by ATM switch. How to design the hardware, software and network management systems of such a switch device that has only one switching platform and one NMS but two sets of control planes at the same time, ATM and MPLS, is studied in details. The application of such a hybrid switch is presented in the last part of the paper.

关键词： ATM MPLS ATM-LSR switch

Adaptive subcarrier and bit allocation based on ant colony optimization

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The Journal of China Universities of posts and telecommunications 2010年第6期17卷 59-64页

作者： ZHAO Ying-hong,XU Xiao-dong,HAO Zhi-jie,TAO Xiao-feng Wireless Technology Innovation Institute,Key Laboratory of Universal Wireless Communication,Ministry of Education,beijing university of {2. and telecommunications,beijing 100876,China [a] Wireless Technology Innovation Institute Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts telecommunications Beijing 100876 China

The problem of resource allocation in multiuser orthogonal frequency division multiplexing （OFDM） system is a combinatorial optimization problem,difficult to obtain optimal solutions in polynomial time. For the sake of reducing complexity,it can be solved either by relaxing constraints and making use of linear algorithms or by metaheuristic methods. In this paper,an algorithm based on ant colony optimization （ACO）,which is a typical algorithm of metaheuristic methods,is proposed for the problem,utilizing excellent search performance of ACO to obtain good solutions. In addition,a parameter is applied to balance the efficiency and fairness of resource allocation. Performance analysis between algorithms based on ACO and genetic algorithm （GA） is carried out,indicating that the proposed algorithm based on ACO outperforms traditional linear algorithms as well as GA in the system throughput with assurance of fairness simultaneously,being as a promising technology for OFDM resource allocation.

关键词： ACO OFDM GA

A dynamic fuzzy clustering method based on genetic algorithm

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Progress in Natural science:Materials International 2003年第12期 52-55页

作者： ZHENG Yan 1*, ZHOU Chunguang 2. LIANG Yanchun 2.and GUO Dongwei 2.1. College of Computer science and Technology, beijing university of posts and telecommunications,{2., China 2. College of Computer science and Technology, Jilin university, Changchun 130012. China) College of Computer science and Technology Beijing University of Posts and Telecommunications Beijing 100876 China College of Computer science and Technology Jilin University Changchun 130012 China

A dynamic fuzzy clustering method is presented based on the genetic algorithm. By calculating the fuzzy dissimilarity between samples the essential associations among samples are modeled factually. The fuzzy dissimilarity between two samples is mapped into their Euclidean distance, that is, the high dimensional samples are mapped into the two dimensional plane. The mapping is optimized globally by the genetic algorithm, which adjusts the coordinates of each sample, and thus the Euclidean distance, to approximate to the fuzzy dissimilarity between samples gradually. A key advantage of the proposed method is that the clustering is independent of the space distribution of input samples, which improves the flexibility and visualization. This method possesses characteristics of a faster convergence rate and more exact clustering than some typical clustering algorithms. Simulated experiments show the feasibility and availability of the proposed method.

关键词： dynamic fuzzy clustering fuzzy dissimilarity matrix genetic algorithm fuzzy c means clustering.